/* FCE Ultra - NES/Famicom Emulator
 *
 * Copyright notice for this file:
 *  Copyright (C) 2002 Xodnizel
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 */

/****************************************************************/
/*                        FCE Ultra                                */
/*                                                                */
/*        This file contains routines for reading/writing the     */
/*        configuration file.                                        */
/*                                                                */
/****************************************************************/

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "../../fceu-types.h"
#include "config.h"

static int FReadString(FILE *fp, char *str, int n) {
	int x = 0, z;
	for (;; ) {
		z = fgetc(fp);
		str[x] = z;
		x++;
		if (z <= 0) break;
		if (x >= n) return 0;
	}
	if (z < 0) return 0;
	return 1;
}

static void GetValueR(FILE *fp, char *str, void *v, int c) {
	char buf[256];
	int s;

	while (FReadString(fp, buf, 256)) {
		fread(&s, 1, 4, fp);
		if (!strcmp(str, buf)) {
			if (!c) { // String, allocate some memory.
				if (!(*(char**)v = (char*)malloc(s)))
					goto gogl;
				fread(*(char**)v, 1, s, fp);
				continue;
			}else if (s > c || s < c) {
 gogl:
				fseek(fp, s, SEEK_CUR);
				continue;
			}
			fread((uint8*)v, 1, c, fp);
		}else
			fseek(fp, s, SEEK_CUR);
	}
	fseek(fp, 4, SEEK_SET);
}

static void SetValueR(FILE *fp, char *str, void *v, int c) {
	fwrite(str, 1, strlen(str) + 1, fp);
	fwrite((uint8*)&c, 1, 4, fp);
	fwrite((uint8*)v, 1, c, fp);
}

static void SaveParse(CFGSTRUCT *cfgst, FILE *fp) {
	int x = 0;

	while (cfgst[x].ptr) {
		if (!cfgst[x].name) {   // Link to new config structure
			SaveParse((CFGSTRUCT*)cfgst[x].ptr, fp);     // Recursion is sexy.  I could
			// save a little stack space if I made
			// the file pointer a non-local
			// variable...
			x++;
			continue;
		}

		if (cfgst[x].len)               // Plain data
			SetValueR(fp, cfgst[x].name, cfgst[x].ptr, cfgst[x].len);
		else                            // String
		if (*(char**)cfgst[x].ptr)      // Only save it if there IS a string.
			SetValueR(fp, cfgst[x].name, *(char**)cfgst[x].ptr,
					  strlen(*(char**)cfgst[x].ptr) + 1);
		x++;
	}
}

void SaveFCEUConfig(char *filename, CFGSTRUCT *cfgst) {
	FILE *fp;

	fp = fopen(filename, "wb");
	if (fp == NULL) return;

	SaveParse(cfgst, fp);

	fclose(fp);
}

static void LoadParse(CFGSTRUCT *cfgst, FILE *fp) {
	int x = 0;

	while (cfgst[x].ptr) {
		if (!cfgst[x].name) {   // Link to new config structure
			LoadParse((CFGSTRUCT*)cfgst[x].ptr, fp);
			x++;
			continue;
		}
		GetValueR(fp, cfgst[x].name, cfgst[x].ptr, cfgst[x].len);
		x++;
	}
}

void LoadFCEUConfig(char *filename, CFGSTRUCT *cfgst) {
	FILE *fp;

	fp = fopen(filename, "rb");
	if (fp == NULL) return;
	LoadParse(cfgst, fp);
	fclose(fp);
}
